Conventionally, a layered body of a combined glass type has been used for a transparent member having durability. The combined glass type layered body is widely used as window glasses for vehicles such as cars, aircrafts and buildings since it is safe in that even though it is damaged by external impact, the glass debris resist shattering. For such combined glass type layered body, one is used which comprises an intermediate film for the combined glass in between at least one pair of glass. For the intermediate film for the combined glass, for example, a polyvinyl butyral intermediate film and an ethylene-vinyl acetate copolymer intermediate film are generally known, and a vinyl chloride resin intermediate film is also considered.
On one hand, there is a growing demand for displaying by projection, car navigation on window glass of vehicles such as cars and displaying by projection, merchandise information, advertisement, or the like on a shop window of a department store, or the like, or on a transparent partition of an event venue, or the like while maintaining the transparency thereof. However, no projector screens of a combined glass type existed, capable of visualizing the image which has been projected by a projector, while maintaining the safety and transparency as a combined glass type layered body.
However, since a conventional projector screen has a low transparency, there is a technical problem that such projector screen cannot be applied to a transparent partition, or the like. Therefore, various proposals have been made as below. There is proposed a screen having a concave portion on the surface as a projector screen (see Patent Document 1). A double face image film screen is proposed, comprising a transparent material of any one kind selected from the group of polyester, acryl, and polycarbonate; and a light refractive material of silica, contained in or coated on such transparent material, and characterized in removing a hot spot (see Patent Document 2). A transmission type screen layered body is proposed, which is capable of easily attaching a transmission type screen when attaching thereof by water to an attached substrate, such as a glass or a plastic board, and capable of peeling off a light diffusion layer from the attached substrate without any remainings thereof (see Patent Document 3). A transmission type screen is proposed, wherein a Fresnel lens sheet/a lenticular lens sheet/a light diffusion sheet are arranged in this order, wherein the light diffusion sheet is a combined glass having an intermediate resin film layer between two glass board-form bodies and the haze is from 15 to 80% (see Patent Document 4). A transmission type screen is proposed, comprising a transparent thin film layer comprising diamond microparticles with a median diameter of from 0.01 to 1 μm obtained by oxidation treatment of nanodiamonds having a graphite phase obtained from exposure method (see Patent Document 5). A transparent light diffusion body is proposed, containing a thin film (from 0.2 to 400 μm), which nanoparticles of a high refractive index are dispersed in a dispersion medium to obtain a highly transparent transmission type screen (see Patent Document 6).